> The problem with any immigration service in the world is that they are dealing with non-citizens which lack most protections citizenship would have given them
No, this is specifically a problem with the US if they withhold many those rights to non citizens. In developed countries existing as a person gives you those rights, not citizenship.
The US does not recognize non-immigrant (tourist/student/some work visas) aliens to be people, thus they don't have all the rights the people have like bearing arms (which is ascribed to people like the 4th amendment does, unlike elsewhere where sometimes citizens is used).
Again it uses 'the people' in the 4th amendment though, which is usually argued as applying generally to people without a difference. Based on wording 2A and 4A applies to tourists, or neither do.
No, this is specifically a problem with the US if they withhold many those rights to non citizens. In developed countries existing as a person gives you those rights, not citizenship.